From df4265707999b08d220374c08e82711f264247bf Mon Sep 17 00:00:00 2001 From: Yawning Angel Date: Fri, 3 Apr 2015 14:21:31 +0000 Subject: Move logging wrappers into common/log, and add a DEBUG log level. Implements feature #15576. --- common/log/log.go | 179 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 179 insertions(+) create mode 100644 common/log/log.go (limited to 'common') diff --git a/common/log/log.go b/common/log/log.go new file mode 100644 index 0000000..5d0a146 --- /dev/null +++ b/common/log/log.go @@ -0,0 +1,179 @@ +/* + * Copyright (c) 2014-2015, Yawning Angel + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * * Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * + * * Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +// Package log implements a simple set of leveled logging wrappers around the +// standard log package. +package log + +import ( + "fmt" + "io/ioutil" + "log" + "net" + "os" + "strings" +) + +const ( + elidedAddr = "[scrubbed]" + + levelError = iota + levelWarn + levelInfo + levelDebug +) + +var logLevel = levelInfo +var enableLogging bool +var unsafeLogging bool + +// Init initializes logging with the given path, and log safety options. +func Init(enable bool, logFilePath string, unsafe bool) error { + if enable { + f, err := os.OpenFile(logFilePath, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0600) + if err != nil { + return err + } + log.SetOutput(f) + } else { + log.SetOutput(ioutil.Discard) + } + enableLogging = enable + return nil +} + +// SetLogLevel sets the log level to the value indicated by the given string +// (case-insensitive). +func SetLogLevel(logLevelStr string) error { + switch strings.ToUpper(logLevelStr) { + case "ERROR": + logLevel = levelError + case "WARN": + logLevel = levelWarn + case "INFO": + logLevel = levelInfo + case "DEBUG": + logLevel = levelDebug + default: + return fmt.Errorf("invalid log level '%s'", logLevelStr) + } + return nil +} + +// Noticef logs the given format string/arguments at the NOTICE log level. +func Noticef(format string, a ...interface{}) { + if enableLogging { + msg := fmt.Sprintf(format, a...) + log.Print("[NOTICE]: " + msg) + } +} + +// Errorf logs the given format string/arguments at the ERROR log level. +func Errorf(format string, a ...interface{}) { + if enableLogging && logLevel >= levelError { + msg := fmt.Sprintf(format, a...) + log.Print("[ERROR]: " + msg) + } +} + +// Warnf logs the given format string/arguments at the WARN log level. +func Warnf(format string, a ...interface{}) { + if enableLogging && logLevel >= levelWarn { + msg := fmt.Sprintf(format, a...) + log.Print("[WARN]: " + msg) + } +} + +// Infof logs the given format string/arguments at the INFO log level. +func Infof(format string, a ...interface{}) { + if enableLogging && logLevel >= levelInfo { + msg := fmt.Sprintf(format, a...) + log.Print("[INFO]: " + msg) + } +} + +// Debugf logs the given format string/arguments at the INFO log level. +func Debugf(format string, a ...interface{}) { + if enableLogging && logLevel >= levelDebug { + msg := fmt.Sprintf(format, a...) + log.Print("[DEBUG]: " + msg) + } +} + +// ElideError transforms the string representation of the provided error +// based on the unsafeLogging setting. Callers that wish to log errors +// returned from Go's net package should use ElideError to sanitize the +// contents first. +func ElideError(err error) string { + // Go's net package is somewhat rude and includes IP address and port + // information in the string representation of net.Errors. Figure out if + // this is the case here, and sanitize the error messages as needed. + if unsafeLogging { + return err.Error() + } + + // If err is not a net.Error, just return the string representation, + // presumably transport authors know what they are doing. + netErr, ok := err.(net.Error) + if !ok { + return err.Error() + } + + switch t := netErr.(type) { + case *net.AddrError: + return t.Err + " " + elidedAddr + case *net.DNSError: + return "lookup " + elidedAddr + " on " + elidedAddr + ": " + t.Err + case *net.InvalidAddrError: + return "invalid address error" + case *net.UnknownNetworkError: + return "unknown network " + elidedAddr + case *net.OpError: + return t.Op + ": " + t.Err.Error() + default: + // For unknown error types, do the conservative thing and only log the + // type of the error instead of assuming that the string representation + // does not contain sensitive information. + return fmt.Sprintf("network error: <%T>", t) + } +} + +// ElideAddr transforms the string representation of the provided address based +// on the unsafeLogging setting. Callers that wish to log IP addreses should +// use ElideAddr to sanitize the contents first. +func ElideAddr(addrStr string) string { + if unsafeLogging { + return addrStr + } + + // Only scrub off the address so that it's easier to track connections + // in logs by looking at the port. + if _, port, err := net.SplitHostPort(addrStr); err == nil { + return elidedAddr + ":" + port + } + return elidedAddr +} -- cgit v1.2.3